1. Field of the Invention
The present invention relates to a vacuum cleaner. More particularly, the present invention relates to a cyclone dirt separating apparatus, which is applicable to a vacuum cleaner and filters dirt drawn in together with air using a centrifugal force in two or more steps and a vacuum cleaner with the same.
2. Description of the Related Art
A cyclone dirt separating apparatus has a structure by which a circular air current is formed in a cyclone chamber to separate the dirt from the air using a centrifugal force, the dirt is collected and the clean air is discharged to an exterior. Recently, in order to enhance the dirt collection efficiency, a multi cyclone dirt separating apparatus, which separates the dirt contained in the air in at least two steps, has been introduced.
FIG. 1 and FIG. 2 are views showing one example of a cyclone dirt separating apparatus disclosed in Korean Patent Application No. 2003-62520 filed in the name of the same applicant. FIG. 1 is a schematic perspective view of the upright type vacuum cleaner to which the multi cyclone dirt separating apparatus is applied and FIG. 2 is an exploded perspective view of the multi cyclone dirt separating apparatus in FIG. 1.
A motor mounting space 23 is provided in a main body 21 of the vacuum cleaner. A suction nozzle 24 is connected to a lower side of the main body 21 of the vacuum cleaner and a cyclone mounting section 22 is provided at a center portion of a front side of the main body 21 of the vacuum cleaner. On the other hand, an air suction passage 25 and an air discharge passage 26 are formed at a rear side of the cyclone mounting section 22 in a substantially vertical direction. Once a multi cyclone dirt separating apparatus 10 is mounted to the cyclone mounting section 22, the air suction passage 25 and the air discharge passage 26 are in fluid communication with an air inlet tube 11 and an air outlet tube 12, respectively.
Referring to FIG. 2, the multi cyclone dirt separating apparatus 10 comprises a first cyclone 13 for preliminarily separating dirt from the drawn-in air and a plurality of second cyclones 14 at a periphery of the first cyclone 13 for surrounding the first cyclone 13. And, the multi cyclone dirt separating apparatus 10 further comprises an air outlet port 15 formed at an upper side of the first cyclone 13 and the second cyclones 14; an inflowing/outflowing cover 17 communicating air inlet ports 16 of the second cyclones 14 with each other; a cyclone cover 18 provided on the inflowing/outflowing cover 17 and having the air outlet tube 12 formed thereon; and a dirt collecting case 19 for collecting dirt separated from the air in the first and second cyclones 13 and 14.
An operation of the multi cyclone dirt separating apparatus 10 and the vacuum cleaner having the structure as described above is described as follows.
First, once a suction force is generated in the main body 21 of the vacuum cleaner, the air containing dirt is passed through the suction nozzle 24 and the air suction passage 25 and then enters the multi cyclone dirt separating apparatus 10 through the air inlet tube 11.
Air passed through the air inlet tube 11 enters the first cyclone 13 in a tangential direction. A circular current is formed by the air while the air descends, and large sized dirt is separated from the air to collect in the dirt collecting case 19. The air from which the large sized dirt is separated ascends again and is discharged through the air outlet port 15 of the first cyclone 13. The air is then passed through an air passage (not shown) of the inflowing/outflowing cover 17 and enters each second cyclone 14 through the air inlet port 16. And, the air in the second cyclone 14 forms a circular current again and descends, small sized dirt separated from the air is collected in the dirt collecting case 19.
The air from which the small sized dirt is separated ascends and is passed through each discharge passage 17a of the inflowing/outflowing cover 17 and then collected in the cyclone cover 18. The air is discharged to an exterior of the multi cyclone dirt separating apparatus 10 via the air outlet tube 12 formed on the cyclone cover 18. Thereafter, the air is passed through the air discharge passage 26 and the motor mounting space 23 and then discharged to an exterior of the main body 21 of the vacuum cleaner.
However, the conventional multi cyclone dirt separating apparatus with the structure as mentioned above has the drawbacks as follows.
First, the air inlet tube 11 through which the air is entered is provided at an upper side wall of the first and second cyclones 13 and 14, and, in general, the air outlet tube 12 through which the air is discharged is provided at an upper side or a side portion of the cyclone cover 18 covering the first and second cyclones 13 and 14. However, since the above structure causes the problems that an entire height of the multi cyclone dirt separating apparatus 10 is increased, it is hard to design a compact canister type vacuum cleaner.
Second, the motor used for the vacuum cleaner, in particular, the upright vacuum cleaner is very heavy in weight, and so the motor mounting space 23 is provided generally at a lower side of the main body 21 of the vacuum cleaner. Accordingly, the motor mounting space 23 is located at a lower side of the cyclone mounting section 22. On the other hand, since the air outlet tube 12 is placed at an upper side of the multi cyclone dirt separating apparatus 10, the air discharging passage 26 communicating the motor mounting space 23 with the air outlet tube 12 should have a long length. Due to this constitution, a loss of suction force generated in the motor mounting space 23 is increased, and so a pressure loss is increased. Also, an inner structure of the main body 21 of the vacuum cleaner becomes complicated.